1. Field of the Invention
The present invention generally relates to moving systems for mobility-impaired individuals, and more particularly to a configurable lift chair which allows the user to be acquired from or transferred to a position adjacent the lift chair in either a sitting or laying position.
2. Description of the Related Art
In the United States alone, there are millions of physically challenged individuals who are confined to wheelchairs due to illness, accidents or degenerative diseases. While some these people are able to stand on their own, many are unable to support their weight on their legs. People who are unable to stand or otherwise lift their weight with their arms face many difficulties in their daily lives. One of the most serious of these is that they must be frequently lifted and transferred between their wheelchairs and their beds, regular chairs, dining facilities, bathroom fixtures, cars, etc. In nursing homes for example, it is estimated that patients must be lifted and transferred 8 to 15 times per day depending on their illness and physical condition.
Lifting and moving these individuals usually is done by family members, friends or professional care givers in home care situations, and by trained nurses or therapists in institutional settings. Occasionally, commercially available lifting aids are employed to assist with patient lifting, but because of limitations and ease of use issues, most patient lifting and transfers are done manually. Whenever disabled individuals are lifted or moved, there is a possibility for injuring that person. These injuries usually result when the patient is bumped into objects while being lifted and transferred, or from being dropped.
When caregivers manually lift and transfer patients, they can also seriously injure themselves, particularly their backs. Often the patient being lifted is significantly heavier than the care giver, and cannot assist the care giver during the move. Some patients move erratically while being moved and may slip out of the care givers grasp, forcing the care giver to quickly readjust her lifting position. Lifting and moving heavy (bariatric) patients is a major reason many nurses have left that profession.
There are several mechanized patient lift and transfer systems which provide an alternative for lifting and transferring a patient or mobility-impaired individual. However, these devices and systems have serious shortcomings, and do not address the total need associated with safely lifting, transferring, and transporting handicapped individuals within their daily living and healthcare environments. One device commonly used is a hoist or crane in which the patient is supported in a flexible sling. This device, referred to generically as a Hoyer lift, consists of a pivoted arm mounted to a base having casters. The arm can be moved by a hydraulic cylinder, and the patient lifting sling is typically attached to the end of the arm by a lifting bridle. One example of such a lift is illustrated in U.S. Pat. No. 3,940,808.
While the Hoyer-type lift designs are fairly simple and thus relatively inexpensive, they can cause serious discomfort or injury for the mobility-impaired individual. If a sling is used to carry the individual, it places the patient in an awkward position under compression. Patients have also characterized sling transfers as undignified and humiliating. Lift designs which use rigid supports, such as the foldable seat panels in the '808 patent, create very high localized shear and pressure stresses on the patient which can lead to skin breakdown (especially in the elderly) and to the generation of painful pressure ulcers or bed sores.
Another significant problem with lift designs is the requirement that the patient support feature (e.g., sling or seat) be pre-positioned under the patient prior to deployment of the device. This requirement entails significant manual moving, lifting, and/or rolling of the patient by a caregiver to properly prepare for acquisition by the lift. Such manual manipulation of the patient can be both uncomfortable and unsafe for the patient as well as for the caregiver. During this preparation process, injuries to the patient resulting from falling off the side of the bed are common. Such patient manipulation also increases the likelihood of contagion, i.e., nosocomial infections such as antibiotic-resistant staph, creating additional risk for the patient.
Alternative patient moving systems have been devised which attempt to remove the requirement of pre-positioning a patient support feature. Many of these systems rely on one or more webs or belts which move as the system acquires or delivers the user in order to reduce frictional engagement. One example of such a patient-moving device is illustrated in U.S. Pat. No. 4,794,655. Upper and lower belts circulate around upper and lower plates, and are let out or taken up as the upper and lower plates are extended or retracted alongside the patient. The '655 transfer table can further be divided into three sections whose orientation can be adjusted for a sitting position. The lifting/transferring device of U.S. Pat. No. 3,967,328 is similar but uses a single plate and an endless belt. In the invalid transfer device of U.S. Pat. No. 3,871,036, the belt circulates longitudinally rather than transversely. Another transfer system that combines a scoop-like lift with conveyor belts is illustrated in U.S. Pat. No. 6,971,126.
While these devices ideally avoid patient-caregiver contact, they work imperfectly and the caregiver usually must still do some amount of jostling of the patient as well as the transfer device. Moreover, these designs suffer from other significant disadvantages. All of these devices require unobstructed access to the individual resting on the bed. If the sides of the bed have immovable features such as rails, they prevent horizontal progress of the moving transfer table. The transfer tables themselves are rigid and so present the high localized pressure stresses on the patient as noted above. In the '126 patent, the patient support is provided by underlying rollers instead of a table but the rollers are still rigid and generally uncomfortable. The transfer tables and other complexities of these designs further contribute to increased weight of the transfer device, often making it too heavy for manual locomotion and thus requiring a motorized system.
In light of the foregoing, it would be desirable to devise an improved patient lifting and moving device that could integrate all the desired functions in the moving cycle (lift, transfer, and transport) into a single product, while maintaining patient comfort and safety. The device would ideally be able to acquire or deliver a patient in spite of obstructions around the patient's bed or chair. If such easy-to-use, safe, and cost-effective equipment were available to allow friends and family to care for their loved ones at home, healthcare (nursing home) costs would drop significantly, and ill and disabled patients would lead happier, more comfortable lives.